11 year-old girl presenting a 3 cm exophytic indurated inflammatory lesion at the base of the neck. Initial evaluation with ultrasound and MRI demonstrated an heterogenous, highly vascularized lesion with calcifications. Initial diagnosis was dermatofibrosarcoma protuberans.
F18-FDG PET/CT demonstrated a heterogenous exophytic lesion with SUVmax between 4.5 and 8.8. Multiples inactive subcutaneous nodules were found.
The lesion was removed and the diagnosis was pilomatricoma (calcifying epithelioma of Malherbe), with the presence of island of epithelioid cells, shadow cells and calcifications. This benign lesion originates from the hair follicle matrix. It represents 0.12% of all cutaneous lesions but is not infrequent in children, as the vast majority occurs in patients under the age of 21. The location of predilection is the head and neck region. Treatment is by surgical excision with low recurrence rate. Some cases imaged with FDG have been reported in adults but not yet in children.
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